Genome hunting of carbonyl reductases from Candida glabrata for efficient preparation of chiral secondary alcohols

In this work, genome hunting strategy was adopted in screening for reductases from Candida glabrata. A total of 37 putative reductases were successfully expressed in E. coli BL21(DE3). A substrate library containing 32 substrates was established for characterization of each reductase by average specific activity and Shannon-Wiener index. Among them, Cg26 was identified with the highest efficiency and wider substrate spectrum in the reduction of prochiral ketones, with average activity and Shannon-Wiener index of 8.95U·mg-1 and 2.82. Cg26 is a member of 'extended' short chain dehydrogenase/reductase superfamily. Ni2+ could improve its activity. As much as 150g·L-1 ethyl 2-oxo-4-phenylbutyrate could be completely converted by 10g·L-1 Cg26. This study provides evidence for this newly identified Cg26 in the preparation of chiral secondary alcohols.